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https://chanakyajayabalan.wordpress.com/2012/01/09/one-or-more-field-types-are-not-installed-properly-go-to-list-settings-page-to-delete-these-fields-error-while-viewing-manage-content-structure-page/
One or more field types are not installed properly. Go to List settings page to delete these fields. Error while viewing Manage Content and Structure Page